Motorcycle muffler baffle

ABSTRACT

A baffle is provided for a motorcycle muffler to increase the engine horsepower and torque. The baffle includes an elongated pipe with louvered openings, and support members to mount the pipe inside the muffler. The pipe also includes a pair of rods extending spirally along the inner wall of the pipe. The rods are offset 180° from each other. The spiraling rods create an air flow vortex for exhaust gases passing through the baffle, and thereby enhance engine performance.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C.§119 to ProvisionalApplication Ser. No. 61/936,496 filed Feb. 6, 2014, herein incorporatedby reference in its entirety.

BACKGROUND OF THE INVENTION

The exhaust system of a motorcycle is important to engine performance.Conventional motorcycle exhaust systems include header pipes attached tothe exhaust manifold of the engine. The header pipes direct exhaustgases toward the exhaust pipe, which leads to the muffler. The mufflerhelps control the hot gases, as well as the tone and sound from theexhaust.

Motorcycle muffler baffles are well-known in the art and take manyforms. The baffles are mounted inside the muffler or exhaust pipe, andaffects both sound and performance. More particularly, the purpose ofmotorcycle exhaust baffles is two-fold: A baffle quiets the exhaustnoise produced by the engine, and provides back pressure towards theengine. The exhaust baffle routes the exhaust gas exiting the enginethrough a chamber that reduces noise and maintains back pressure.

Baffles generally have a series of holes through which the exhaust gasis passed. The holes slow the flow of the exhaust gases and alter thesound waves. The disruption of the gas flow changes the noise toneproduced by the engine's release of exhaust. The shape and design of thebaffle holes affect the throat roar or rumble of the motorcycle.

Motorcycle engines are normally tuned for back pressure created by thebaffles. The baffle back pressure affects the engine performance,including idling, horsepower, torque, throttle response, andacceleration.

Accordingly, a primary objective of the present invention is theprovision of an improved baffle for a motorcycle muffler.

Another objective of the present invention is the provision of amotorcycle muffler baffle which improves performance of the engine.

Yet another objective of the present invention is the provision of amuffler baffle for motorcycles which increases horsepower and torque ofthe engine.

A further objective of the present invention is the provision of abaffle for a motorcycle muffler which has spiraling louver openings anda pair of internal spiraling rods to induce a vortex air flow within thebaffle.

Still another objective of the present invention is the provision of abaffle for a motorcycle muffler having a pair of air flow membersextending in a spiral pattern on the inside wall of the baffle toenhance air flow and improve engine performance.

Another objective of the present invention is the provision of amotorcycle muffler baffle which is economical to manufacture, easy toinstall, and improves the engine performance while providing a desirableexhaust sound.

These and other objectives will become apparent from the followingdescription of the invention.

SUMMARY OF THE INVENTION

The motorcycle muffler baffle of the present invention includes a pipewith a plurality of louvered openings extending in a spiral patternalong the pipe. A pair of spaced apart supports are provided at one endand at the middle of the baffle to mount the baffle in the motorcyclemuffler. The baffle also includes a pair of internal rods on the insidewall of the baffle and spaced 180° apart. The rods extend in a spiralpattern along the length of the baffle pipe. The openings and rodscreate a vortex air flow within the baffle, which improves horsepowerand torque for the engine and provides a pleasing sound for the muffler.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the motorcycle muffler baffle of thepresent invention.

FIG. 2 is a side elevation view of the baffle.

FIG. 3 is a perspective view showing the spiral configuration of theinternal air control rods of the baffle, according to the presentinvention.

FIG. 4 is a side elevation view illustrating the spiraling air controlrods inside the baffle.

FIG. 5 is an end view of the baffle.

FIG. 6 is an exploded view of the baffle components.

FIG. 7 is a graph comparing the horsepower and torque performance of thebaffle of the present invention compared to two prior art baffles.

DETAILED DESCRIPTION OF THE DRAWINGS

The exhaust baffle of the present invention is generally designated inthe drawings by the reference numeral 10. The baffle 10 includes anelongated pipe 12, which may be one piece, or may be formed from twosections of pipe welded together. The pipe 12 includes a plurality oflouvered openings 14, which are preferably formed in a spiral patternalong the length of the pipe 12. The holes 14 are formed in axiallyextending rows, as best seen in FIG. 2, with each row being offsetrelative to the adjacent row, so as to create the spiral path of theholes 14. The louvered formation of the openings 14 allow exhaust gas toflow outwardly from the interior of the pipe 12.

A first muffler support 16 is provided at the tail end of the pipe 12,and a second muffler support 18 is provided approximately at themidpoint of the baffle 10. The supports 16, 18 facilitate mounting ofthe baffle 10 in a motorcycle muffler (not shown) in any convenientmanner. The tail support 16 has a tapered wall 17 and an increaseddiameter outlet which allows exhaust gas to expand as the gas exits thesupport 16.

A pair of air flow members or rods 20 are welded or otherwise secured onthe inside wall of the pipe 12. Preferably, the rods 20 extend in aspiral pattern within the pipe 12, along substantially the full lengthof the pipe 12. The rods are spaced or offset approximately 180° fromone another. The rods function to control air flow through the pipe 12.It is understood that as an alternative to the rods, the air flow membercould be a flange or small L-shaped member fixed inside the pipe toinduce a vortex air flow for the exhaust gases.

In a preferred embodiment, the pipe 12 is made from 18 gauge milledsteel 18 inches in length, with a 2.25 inch outside diameter. The rods20 are preferably 0.25 inch in diameter. In the preferred method ofinstallation, ⅛ inch holes are drilled or formed in the baffle pipe 12to allow the rods 20 to be tack welded to the inside wall of the pipe12. After assembly, the pipes 12 are powder coated to maintain theintegrity of the metal, and then bolted inside the muffler body.

The baffle 10 improves performance of the motorcycle engine. Theinternal spiral rods 20 in the baffle 10 enhance the engine performanceby creating a swirling vortex action for the exhaust gases, therebyincreasing the horsepower and the torque from the motorcycle engine. Ina dynojet performance evaluation test, the baffle 10 had higherhorsepower and torque of the engine, compared to a stock motorcyclemuffler and a commercially available muffler from Rinehart, as shown inFIG. 7. In FIG. 7, Applicant's torque and horsepower results arerepresented by the upper lines, while the commercially available bafflesare designated by the middle and lower lines. Applicant's maximumhorsepower was 74.84 with the baffle 10, compared to 68.28 and 61.25 forthe commercial baffles. Applicant's maximum torque in this test was92.33, compared to the commercial torque of 81.67 and 76.65 for theprior art baffles.

The invention has been shown and described above with the preferredembodiments, and it is understood that many modifications,substitutions, and additions may be made which are within the intendedspirit and scope of the invention. From the foregoing, it can be seenthat the present invention accomplishes at least all of its statedobjectives.

What is claimed is:
 1. A motorcycle muffler baffle, comprising: a pipewith a plurality of louvered openings extending along the pipe; a firstinternal rod extending in a spiral pattern within the pipe; and a pairof spaced apart supports for mounting the baffle in a motorcyclemuffler.
 2. The motorcycle muffler baffle of claim 1 wherein thelouvered openings extend in a spiral pattern around the pipe.
 3. Themotorcycle muffler baffle of claim 1 wherein the spiral patterns of therod induces a vortex air flow of exhaust gasses within the pipe.
 4. Themotorcycle muffler baffle of claim 1 wherein the spiral pattern of therod extends more than 180° along the pipe.
 5. The motorcycle mufflerbaffle of claim 1 further comprising a second internal rod extending ina spiral pattern within the pipe.
 6. The motorcycle muffler baffle ofclaim 5 wherein the first and second rods are offset approximately 180°from one another.
 7. The motorcycle muffler baffle of claim 1 whereinthe supports have a larger diameter than the pipe.
 8. The motorcyclemuffler baffle of claim 1 wherein the louvered openings are arranged ina plurality of straight lines along the length of the pipe.
 9. Themotorcycle muffler baffle of claim 1 wherein the louvered openings areoriented in axial lines.
 10. The motorcycle muffler baffle of claim 1wherein one support is adjacent an end of the pipe and the other supportis located at an approximate midpoint between opposite ends of the pipe.11. A baffle for a motorcycle muffler, comprising: an elongated pipehaving opposite ends and opposite inner and outer wall surfaces; atleast one support member on the pipe to mount the pipe inside themuffler; a plurality of holes in the pipe extending substantially alongthe length of the pipe; and first and second air flow members extendingalong the inner wall surface of the pipe to create a vortex air flow forexhaust gases passing through the baffle.
 12. The baffle of claim 11wherein the air flow members extend spirally within the pipe.
 13. Thebaffle of claim 12 wherein the air flow members are offset 180° from oneanother.
 14. The baffle of claim 11 wherein the air flow members arespaced on opposite sides of the pipe.
 15. The baffle of claim 11 whereinthe holes are louvers.
 16. The baffle of claim 11 wherein the pipe has aconstant diameter along its full length.
 17. The baffle of claim 11wherein the holes extend in a spiral pattern.
 18. The baffle of claim 17wherein the air flow members extend substantially the full length of thepipe.
 19. The baffle of claim 11 wherein the air flow members are rods.20. The baffle of claim 19 wherein the rods have a diameter of ¼ inch.